A great and cheap way to experiment with your Fender Blues Jr's tone is to try different tubes. Tubes are one of the few things that are easy to replace and do not require an amp technician. If you want to play with different tubes you can always try a bunch of different brands and keep the ones you like and sell the rest on eBay (or Craigslist). That way you can really get the tone you like.

Many players are not crazy about the stock tubes in the Fender Blues Junior and the Fender Pro Junior (especially the Pro Junior). Some of the popular tube brands to improve your tone are:
· JJ Telsa (people really like these)
· Mullard (A little expensive, but you can get the reissues)
· Tung-Sol (A little expensive, but you can get the reissues)
· Electro-Harmonix

The stock el84 tubes in the Fender Blues Junior and Pro Junior are Groove Tubes.

Also keep in mind that, as with any tube amp, the tubes in your Fender Blues Junior or Pro Junior will burn out over time and will need to be replaced.

Use the menu on the right to browse replacement tubes for you Fender Blues Junior and Pro Junior.